Page:Plates illustrating the natural and morbid changes of the human eye.djvu/31

Rh caused by accumulation of pigment of the choroid. The light brown patches in the pale pink portion of the choroid next this line of pigment, represent groups of stellate pigment cells in the otherwise anæmic and somewhat atrophic choroid.

The bending forwards of the retinal vessels, where they pass from the white figure upon the brown line of pigment, is well marked.

Fig. 23.

Atrophy of the choroid and retina. (By some described as choroiditis pigmentosa, by others as retinitis pigmentosa.)

A portion of the retina, choroid, and sclerotic, from the outer equatorial region, as it appeared after removal from the eyeball. From a myopic person.

The numerous small, somewhat star-shaped, black spots were situated upon the choroid, on a level with the part occupied in health by the hexagonal cells.

The retina, to the naked eye, appeared transparent. On drawing it away from the choroid many of the black spots remained attached to it.

The brown elongated patches, separated from each other by light yellow lines, represent groups of stellate pigment cells of the choroid; and the intervening yellow lines represent the empty transparent veins of the choroid.

The groups of stellate pigment cells along the lower margin of the figure appear as pale brown ill-defined patches ; here the pigment cells were found most atrophic.

Fig. 24.

Atrophy of a portion of the choroid and retina adjoining the optic disc.

The optic disc, occupying the middle of the figure, has a light pink colour.

The veins of the retina appear numerous, large, and unequally dilated. The optic disc is surrounded by a yellowish white, defined, irregularly-shaped figure, which, to the right of the disc, extends across the figure. This figure represents the atrophic part of the choroid, which on dissection was found to be semiopaque and subtended by the sclerotic.

The two black spots (a large and a small one) to the right of the